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Residents of Southern New England are used to snowstorms, including the classic blizzards that can stalk this region like a hunter tracks prey. Such storms, known as nor'easters for the direction that the wind comes from, can shut down areas from New York City to Portland, Maine, and bring damaging coastal flooding, feet of snow, and widespread power outages.

However, even the hardiest of New Englanders are likely growing weary, as the third major nor'easter in a parade of powerful storms is projected to hit beginning Monday night.

This storm is not predicted to track close enough to the coast to spread heavy snow well inland, toward New York and New Jersey, like last week's storm did. But eastern Massachusetts can expect near-blizzard to blizzard conditions by Tuesday morning, with snowfall totals potentially nearing 2 feet in some locations, according to the National Weather Service.

Essentially, the atmosphere is acting like a rechargeable battery, with major storms every three to five days, followed by a period of unusually cool, calm weather.

The new storm will hit at a time when thousands of people are still without power in the region due to the tree and power line damage the last storm caused. Some areas in Massachusetts, Connecticut, Rhode Island, New York, and New Jersey are still littered with downed branches and even entire trees split in half.

This coming storm is not likely to cause nearly as much damage to trees and the electrical infrastructure, since it will bring fluffier snow, rather than the pasty, wet cement of the last nor'easter.

There's still a chance the latest nor'easter will track further away from the coast or closer to it, which would significantly change predicted snowfall amounts, but computer models are honing in on a track off the coast of Cape Cod.

The latest nor'easter will likely end a remarkably stormy run of weather for early March, making this winter bookended by a frigid outbreak around New Years and a snowstorm blitz just before spring, with well above average temperatures sandwiched in between.

Computer model depiction of the Greenland block, outlined by the blue square.

To understand why there has been such a barrage of storms, one must look to the large-scale weather pattern in place across the Northern Hemisphere that led up to this stormy period.

As reported in February, the polar vortex, which is a semi-permanent area of low pressure at high altitudes above the Arctic with strong winds swirling around it, split into two pieces. One lobe of the polar vortex established itself over Siberia and Europe, leading to the "Beast from the East" cold and snow outbreak there. Another slipped into the Western U.S. for a time.

Meanwhile, weird things were happening in the Arctic, where it was record-warm for the month of February. The region may soon set a record for the least amount of sea ice cover present at the end of the winter — also known as the lowest sea ice maximum. This is in keeping with trends toward rapidly increasing air temperatures during winter, and thinner, younger sea ice that covers less area over time.

At the same time, conditions across the Pacific Ocean, including the tropical Pacific, set off a chain of events that altered the shape of the jet stream — the highway of air at upper levels of the atmosphere, which steers storms and helps energize them.

Then, a massive block formed over Greenland, as a pattern of atmospheric pressure over the North Atlantic, known as the North Atlantic Oscillation or NAO, plunged to record negative territory.

When the NAO is in a negative phase, it ups the odds for snowstorms in the eastern U.S. and Europe, although it does not guarantee them. Earlier this month, the NAO index plunged to a record low, which is indicative of how primed the atmosphere is for major storms.

Together, these events set the stage for a fusillade of storms to blast the East Coast, among other parts of the world. The Greenland block is absolutely key to this, since it prevents weather systems from simply slinking off out to sea, and allows different branches of the jet stream to come together, or "phase," and form a rapidly intensifying storm.

Here's how Jason Furtado, an assistant professor of meteorology at the University of Oklahoma, explained what's going on, via email:

The jet stream acts as the storm track. The southward displacement of the polar jet stream across the Eastern US (trough) during Greenland blocking/negative North Atlantic Oscillation (NAO) episodes facilitates storm systems to track across the Midwest or Southeast and eventually off the Eastern Seaboard.

Placing these potent systems over the warm Atlantic waters allows them to rapidly intensify and form Nor’easters. The blocking over the North Atlantic also helps to (a) increase winds from the storm system (pressure gradient) and (b) slow the storm system’s progress to the north and east, sometimes even forcing it out to the south. The offshore tracks for these systems with the block in place allows for cold air to take hold across the Northeast and thus make for rather big snowstorms.

The low pressure area forecast to hit southern New England on Monday night and Tuesday will be the third straight storm to undergo bombogenesis, meaning its minimum central air pressure will drop by at least 24 millibars in 24 hours. Such bomb cyclones are typically accompanied by strong winds, as the air rushes in toward the center of the storm.

Without the Greenland block, it's unlikely that all the ingredients would come together three times in a row for major East Coast storms. Think of it as a matchmaker: The Greenland block is facilitating a hook up between weather disturbances pinwheeling across North America, and raising the odds that they'll meet and get busy somewhere off the Mid-Atlantic coast.

A string of storms like this one is not unheard of in New England, as the atmosphere can fall into a pattern that produces a storm every four or five days. That's why some months appear to be rainy every weekend while the workweek is sunny and gorgeous. Interestingly, this next nor'easter hitting tonight is likely to help change the current weather pattern, with the Greenland block breaking down somewhat in coming days.

What about global warming?

Studies show that there are connections between Arctic climate change and midlatitude weather patterns, particularly cold weather outbreaks in Europe, as well as more stubborn, blocking patterns such as the one we're in the grips of now. However, this is still a contested area of climate science, with some studies showing evidence of links between declining Arctic sea ice and the jet stream, and others failing to detect such connections.

Air temperatures (at 925 hPa) are a record high for the #Arctic freeze season (October - February, >67°N) in this data set

Judah Cohen, the director of seasonal forecasting at AER, a Verisk company, has been studying the potential links between Arctic climate change and extreme weather in the Northeast and Europe, among other areas. His work shows that as the Arctic warms, the odds of heavy snows in the Northeast somewhat paradoxically goes up.

"So though a heavy snowfall in March is not unheard of or rare, it is the frequency of the heavy snowfalls that seems to be changing," he said in an email.

"Also maybe a little more rarer is to have three destructive/disruptive storms in quick succession. But I do think this is consistent with the pattern that follows a polar vortex split over time," he said.

A recent study Cohen contributed to showed that polar vortex splits have become more frequent as Arctic sea ice has declined and Arctic warming has accelerated.

In addition, it's clear, that the impact of nor'easters, including the recent ones, is getting worse due to global warming. This is particularly the case with coastal flooding, since sea level rise is providing storms with a higher launching pad for floods than was the case in previous years. For example, the first of the three storms gave Boston it's third-highest tide level on record, with flooding occurring during at east five high tide cycles up and down the coast from Maine to Connecticut.

Also, global warming is causing seas to warm overall, and air temperatures to increase, which results in an uptick in the amount of available water vapor in the air to power major storms like nor'easters. Precipitation extremes, including heavy snow events during the winter, are becoming more common as the climate continues to change.

Interestingly, global warming might be giving people the impression that heavy snows don't occur as much anymore, making these nor'easters more surprising. As University of Georgia researcher Marshall Shepherd said in an email:

"The string of nor'easters is having a significant impact, but it is somewhat amusing that cold and nor'easters have garnered so much attention, the changes in our climate have made having winter newsworthy."